Does not use body language when interacting (e.g. no eye contact, no change of facial expression, maintains a rigid body posture)
Does not interact with people of the same age or group (e.g. a student makes friends with his teachers but not his classmates)
Lack of spontaneous emotional expression and sharing with others (e.g. does not point at objects; does not play with, touch, and chit-chat with others by his own initiative)
He develops speaking very slowly compared to his peers or has no speech at all (i.e. Does not even communicate with gestures)
Even if he can speak, he still cannot have meaningful or useful conversations with others
He keeps on using peculiar terms or speaking in an very odd way (e.g. using self-invented words, consistently making the same grammar mistakes, speaking in a peculiar accent)
He does not play "make-believe" games or copy other children who are playing
Constant and persistent behavior that cannot be explained (e.g. keeps counting coins, watching bottle cap move, or watching the same video clip again and again)
Insistence on following specific, useless routines and rituals (e.g. must eat the same food prepared the same way in the same way; must always go to school on the same time along the same route doing the same things)
Keeps making the same useless movement without reason (e.g. hand or finger flapping or twisting, or complex whole-body movements)
II. The client has already exhibited the above syndromes before age 3
III. The client does not have Rett's Disorder or Childhood Disintegrative Disorder